The present invention relates to an image processing device, an information storage medium, and the like.
A noise component is normally included in a video image signal. A frame-cyclic noise reduction process is known as a method that reduces such a noise component. Specifically, the amount of motion is detected from the preceding-frame output image and the current input image, and the degree of time averaging is controlled based on the amount of motion. The performance of the frame-cyclic noise reduction process depends on the motion estimation (detection) accuracy. A known motion estimation algorithm calculates the absolute difference in luminance between video image signals, and compares the absolute difference with a motion determination threshold value. For example, JP-A-2005-150903 discloses a method that determines that a motion has occurred when the absolute difference is larger than the motion determination threshold value.